/*
 * Copyright 2002-2010 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System.Text;
using System.Web.UI;

namespace Spring.Web.UI.Validation;

/// <summary>
/// Implementation of <see cref="IValidationErrorsRenderer"/> that
/// displays an error image to let user know there is an error, and
/// tooltip to display actual error messages.
/// </summary>
/// <remarks>
/// <para>
/// This renderer's behavior is similar to Windows Forms error provider.
/// </para>
/// </remarks>
/// <author>Aleksandar Seovic</author>
public class IconValidationErrorsRenderer : AbstractValidationErrorsRenderer
{
    private string iconSrc;

    /// <summary>
    /// Gets or sets the name of the image file to use as an error icon.
    /// </summary>
    /// <remarks>
    /// <para>
    /// Image name should be relative to the value of the <see cref="Spring.Web.UI.Page.ImagesRoot"/>
    /// property, and should not use leading path separator.
    /// </para>
    /// </remarks>
    /// <value>The name of the image file to use as an error icon.</value>
    public string IconSrc
    {
        get { return this.iconSrc; }
        set { this.iconSrc = value; }
    }

    /// <summary>
    /// Renders validation errors using specified <see cref="HtmlTextWriter"/>.
    /// </summary>
    /// <param name="page">Web form instance.</param>
    /// <param name="writer">An HTML writer to use.</param>
    /// <param name="errors">The list of validation errors.</param>
    public override void RenderErrors(Page page, HtmlTextWriter writer, IList<string> errors)
    {
        if (errors != null && errors.Count > 0)
        {
            StringBuilder sb = new StringBuilder();
            string separator = "";
            foreach (string error in errors)
            {
                sb.Append(separator).Append(error);
                separator = "\n";
            }

            writer.AddAttribute(HtmlTextWriterAttribute.Src, page.ImagesRoot + "/" + IconSrc);
            writer.AddAttribute(HtmlTextWriterAttribute.Title, sb.ToString());

            writer.RenderBeginTag(HtmlTextWriterTag.Img);
            writer.RenderEndTag();
        }
    }
}
